A Czochralski crystal growth technique is frequently used to grow single crystals. In this technique, a melt is formed by heating a material in a crucible. A single crystal is then grown by withdrawing a rotating seed crystal that is in contact with the melt. As the seed crystal is withdrawn or pulled from the crucible, the melt solidifies on the seed. A pulling head arrangement, which is part of a crystal growth apparatus, is typically used to pull the single crystal.
An oxyorthosilicate material may be used to form a single crystal. For example, single crystals fabricated from an oxyorthosilicate material may be used in detectors for positron emission tomography (PET) medical scanners utilized in molecular imaging. An oxyorthosilicate crystal is typically grown in the form of a long cylindrical boule.
It is important to be able to measure the weight of the boule during initial stages of boule formation. A boule is relatively light during initial stages of boule formation. Therefore, a scale having sufficient low-end resolution is used to measure the weight of a lightweight boule. However, scales having sufficient low-end resolution do not have sufficient weight to weigh a full size boule having a desired target weight.